COVID-19 Lockdown Help Reduce Air Pollution in Southeast Asia

Jan, 2021 - By SMI

According to previous research, daily carbon dioxide emissions (global) are declined by 17%, owing to the strict lockdown measures.

The virus has evolved into a global pandemic, with more than 964,000 deaths and more than 31 million confirmed cases around the world. The lockdown measures implemented in every corner of the world to curb the spread of the novel coronavirus have helped reduce some airborne pollutants. Moreover, preventive measures such as lockdown have inadvertently led to some positive changes to the environment. The assessment of anthropogenic emissions reduction due to preventive measures imposed by governments (across the globe) is important to determine the impact of the novel coronavirus on economic growth and pollution.

Now, the new research analyzes the effect of lockdown on pollutants and aerosols over the Southeast Asian atmospheric environment. According to previous research, daily carbon dioxide emissions are declined by 17%, owing to the strict lockdown measures. Emissions from surface transport such as car travel, account for around half (43%) of the global emissions reduction during the peak of the lockdown measures. Whereas the emissions from industrial sources and power generation together account for 43% of daily global emissions reduction.

The researchers found that the lockdown resulted in a significant reduction in Aerosol Optical Depth (AOD) over SEA areas and an outflow of pollution in marine areas. Moreover, the team detected large reductions of tropospheric NO2 over urban agglomerations and around 25 to 31%, 9 to 20%, 63 to 64%, 23 to 32%, and 26 to 31% reductions, respectively, in CO, SO2, NO2, PM2.5, and PM10 in urban Malaysia during the lockdown. The level of NO2 decreased to 64% in urban areas and by 33 to 46% in industrial sites. The results showed a significant decrease in AOD over the southern SEA region, including the Philippines, Brunei, Singapore, and Malaysia. The research was published in the Science of the Total Environment journal.